1. Field of the Invention
The present invention relates to a touch sensing apparatus for generating reference sensing data for respective pieces of data among a plurality of pieces of data in consideration of an influence of electrical noise or foreign materials such as water droplets falling onto a panel and calculating effective sensing data from the reference sensing data, thereby precisely determining a touch input, and a data processing method thereof.
2. Description of the Related Art
Touch sensing apparatuses such as a touch screen, a touch pad, and the like, are input apparatuses attached to display apparatuses and provide users with intuitive input methods, and recently have been applied to various electronic devices such as cellular phones, personal digital assistants (PDA), navigation devices, and the like. In particular, as a demand for smart phones has recently increased, touch screens have been increasingly employed as touch sensing apparatuses capable of providing various user input methods in a limited form factor.
Touch screens applied to portable devices can be classified into resistance-type touch screens and capacitance-type touch screens according to methods of sensing a touch input. Capacitance-type touch screens can advantageously have long lifetime and easily implement various input methods and gestures, and thus applications thereof have been increasing. In particular, a multi-touch interface may be easier to implement in capacitance-type touch screens than in resistance-type touch screens, thus having a wide range of applications in devices such as smart phones.
Touch screen apparatuses may include a panel unit and a controller for determining a touch input. The controller converts a change in capacitance generated in the panel unit according to the touch input into sensing data and thus determines the touch input. The controller may determine the touch input from the sensing data indicating a difference in the change in capacitance between a state in which no touch input occurs and a state in which the touch input occurs. Thus, in a case in which reference sensing data indicating the state in which no touch input occurs, changes due to electrical noise or impacts on the panel unit such as those of water droplets, the controller may not precisely determine the touch input.
In the following related art documents, Patent Document 1 relates to a touch screen apparatus and a driving apparatus of a touch panel, and discloses determining a touch input by using a difference in data values between sensing channels Y1˜Yn of a touch screen but does not disclose considering reference data with respect to sensing data corresponding to a adjacent driving channel. Patent Document 2 relates to a touch sensor apparatus and merely discloses determining an effective touch input based on a difference value of adjacent sensing channels but does not disclose considering reference data with respect to sensing data corresponding to an adjacent driving channel.